Re: Query questions

am  31.07.2006, um 15:32:19 +0200 mailte Christian Rengstl folgendes:
> Hi list,
>
> i have a problem with creating a query and i hope somebody can give me
> some hints. I have the following table
> pid(varchar), crit(varchar), val1(varchar), val2(varchar),
> iDate(timestamp)
> where there are up to 63 million lines with 1500 distinct pids and
> around 42000 distinct crits:
> pid   crit   val1   val2   iDate
> 'yyy'  'aaa'  'b'    'c'      someTime
> 'yyy'  'bbb'  'b'    'a'      anotherTime
> ...
> What i have to do is to export the table for which i have to query the
> table with the following pattern: select val1, val2 from mytable where
> pid='yyy' and crit='aaa'. But if i do this 63 million times, it just
> takes too long. So, what i would like to do is to make a query where i

Do you have indexe on pid and crit?
Can you paste a "explain analyse select val1, val2 from mytable where
pid='yyy' and crit='aaa';"

Which version? ("select version();").


HTH, Andreas
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Andreas Kretschmer    (Kontakt: siehe Header)
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